JP2012119858A - Imaging device, imaging method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging device, an imaging method, and a program which enable capturing an image of a good quality by automatically selecting an imaging method corresponding to the scene.SOLUTION: The imaging device sorts an imaged scene on the basis of an image for live viewing captured before a shutter button is pressed. When the imaged scene is sorted as a night view scene, a continuous shooting function is set automatically to be on and whenever a user presses the shutter button once, plural images are captured continuously. Moreover, the images captured continuously are composed such that the content of the composition is switched between when bright and moving fireworks etc. are imaged and when a person is imaged with the bright and moving fireworks etc. as the background.

Description

  The present invention relates to a photographing apparatus, a photographing method, and a program, and in particular, a photographing apparatus, a photographing method, and a photographing method capable of automatically selecting a photographing method according to a scene and photographing a higher quality image. Regarding the program.

  Many digital cameras sold in recent years are equipped with a function capable of shooting in a mode suitable for a shooting scene such as a portrait mode, a landscape mode, and a night view mode. For example, when shooting a landscape, the user can set optimum values for shooting a landscape as the values of various parameters, such as increasing the aperture value simply by selecting the landscape mode.

  There has also been proposed a digital camera that captures a plurality of images in response to the shutter button being pressed once when the night view mode is selected, and combines the obtained plurality of images. By combining a plurality of images, it is possible to obtain an image with an appropriate exposure with an extended dynamic range.

  For example, in Patent Document 1, when shooting a person against a background of a night view, low-sensitivity shooting with flash on and high-sensitivity shooting with flash off are continuously performed. A technique is disclosed in which a person area is extracted from an obtained image and is combined with a person area portion of an image obtained by subsequent shooting.

JP 2005-86488 A

  In the technique disclosed in Patent Document 1, the shutter speed is limited in order to suppress camera shake, and in particular, the night scene portion that is the background may not be properly exposed. In general, when shooting is performed with a shutter speed longer than 1 / focal length, camera shake occurs. Also, when shooting an object that moves brightly in the dark, such as fireworks, as a background, it is necessary for the user to set the shutter speed, which is difficult for general users.

  An object of the present invention is to provide a photographing apparatus, a photographing method, and a program capable of automatically selecting a photographing method according to a scene and photographing a higher quality image.

  One aspect of the present invention is an image capturing unit, a scene classifying unit that analyzes an image captured by the image capturing unit before the shutter button is operated, and classifies a scene that is being captured, and the scene classification. When the scene classified by the means is a night scene that is a scene including a night view as a subject, the photographing means is controlled so that a plurality of images are photographed continuously when the shutter button is operated. And a control means.

  One aspect of the present invention is a shooting method of a shooting apparatus including a shooting unit, wherein a scene that analyzes an image shot by the shooting unit before a shutter button is operated and classifies a scene in which the shooting is performed When the scene classified by the classification step and the scene classification step is a night scene that is a scene including a night scene as a subject, a plurality of images are continuously captured when the shutter button is operated. And a control step for controlling the photographing means.

  According to one aspect of the present invention, in a program for causing a computer to execute a shooting process of a shooting apparatus including a shooting unit, an image shot by the shooting unit is analyzed before a shutter button is operated, and shooting is performed. When a scene classification step for classifying a scene and a scene classified by the processing of the scene classification step are night scenes that include night scenes as subjects, a plurality of images are displayed when the shutter button is operated. The computer is caused to execute processing including a control step of controlling the photographing means so that photographing is continuously performed.

  ADVANTAGE OF THE INVENTION According to this invention, the imaging | photography apparatus, the imaging | photography method, and program which can select the imaging | photography method according to a scene automatically and can image | photograph a higher quality image can be provided.

It is a block diagram which shows the structural example of the imaging device which concerns on this embodiment. It is a figure explaining the function of an imaging device. It is a block diagram which shows the function structural example of an imaging device. It is a figure explaining the determination method whether a to-be-photographed object contains fireworks. It is a figure explaining maximum value composition. It is a figure explaining the flow of extraction of a person area. It is a figure which shows the example of an imaging | photography scene. It is a figure which shows the example of mask data. It is a figure which shows the example of correction of mask data. It is a figure which shows the example of a blend map. It is a flowchart explaining the imaging | photography process of an imaging device. FIG. 12 is a flowchart following FIG. 11 for describing photographing processing of the photographing apparatus.

[Configuration of Shooting Device]
FIG. 1 is a block diagram illustrating a configuration example of a photographing apparatus 1 according to the present embodiment. The photographing apparatus 1 is an apparatus having a still image photographing function, such as a digital still camera, a digital video camera, and a mobile phone.

  A CPU (Central Processing Unit) 11 executes a predetermined program and controls the overall operation of the photographing apparatus 1. As will be described later, the CPU 11 classifies scenes that the user is about to shoot before the shutter button is pressed. The shooting scenes are classified based on live view images captured by a CMOS (Complementary Metal Oxide Semiconductor) sensor 12. When the shutter button is pressed, the CPU 11 controls the CMOS sensor 12 to perform continuous shooting or cause the flash 17 to emit light, and executes a shooting process optimal for the shooting scenes that have been classified in advance.

  The CMOS sensor 12 performs photoelectric conversion of light captured by the lens, and performs A / D (Analog / Digital) conversion of an image signal obtained by the photoelectric conversion. The CMOS sensor 12 stores image data obtained by A / D conversion in the memory 13.

  The image processing unit 14 reads an image captured by the CMOS sensor 12 and stored in the memory 13 before the shutter button is pressed from the memory 13 as a live view image, and displays the image on an LCD (Liquid Crystal Display) 16. In addition, when the CPU 11 classifies that the shooting scene that the user is shooting is a night scene, the image processing unit 14 synthesizes a plurality of images that are continuously shot in response to the shutter button being pressed. For example, one composite image is output to the output unit 15 or the LCD 16. Information representing the classification result of the shooting scene is supplied from the CPU 11 to the image processing unit 14. Further, when the CPU 11 classifies that the shooting scene that the user is going to shoot is a normal scene such as an outdoor scene instead of a night view, the image processing unit 14 captures one image and performs white balance on the captured image. Various image processing such as processing and contour enhancement processing are performed.

  The output unit 15 stores the composite image generated by the image processing unit 14 in a memory card that can be attached to and detached from the photographing apparatus 1 or transmits it to an external device. The LCD 16 displays the live view image or the composite image supplied from the image processing unit 14.

  The strobe 17 emits light according to control by the CPU 11 and irradiates the subject with light. The operation unit 18 includes various buttons such as a shutter button. When the button is operated, the operation unit 18 outputs a signal representing the content of the user operation to the CPU 11.

  FIG. 2 is a diagram conceptually showing the photographing process of the photographing apparatus 1 having the above configuration. When the shooting scene is classified as a night scene, the continuous shooting function is automatically set to ON, and a plurality of images are continuously displayed as shown in FIG. 2 in response to the user pressing the shutter button once. An image is taken. In the example of FIG. 2, two images are obtained by the continuous shooting function.

  Further, as described above, the continuously captured images are combined in the image capturing apparatus 1, and the content of the combining processing is, for example, a bright and moving firework as indicated by the tip of arrow # 1. And a case where a person is photographed against a background of bright and moving fireworks as indicated by the tip of arrow # 2. Hereinafter, a case where a subject moving brightly with respect to the background is fireworks will be described, but the same processing can be applied to photographing other subjects such as a headlight of an automobile.

  FIG. 3 is a block diagram illustrating a functional configuration example of the imaging apparatus 1 for realizing the imaging process described with reference to FIG. At least a part of the functional units shown in FIG. 3 is realized by the CPU 11 shown in FIG. 1 executing a predetermined program.

  As shown in FIG. 3, in the photographing apparatus 1, a scene classification unit 31, a face detection unit 32, and a photographing control unit 33 are realized. Images captured by the CMOS sensor 12 and stored in the memory 13 are input to the scene classification unit 31 and the face detection unit 32.

  The scene classification unit 31 analyzes an image captured for live view before the shutter button is pressed, and the user selects a plurality of preset scenes such as a portrait scene, a landscape scene, and a night scene. Classify the scene you are about to shoot. For example, if an image with a number of skin color pixels greater than the threshold is captured, the scene is classified as a portrait scene, and if an image with more green or sky blue pixels than the threshold is captured, Is classified as a landscape scene. When an image in which the number of black pixels is larger than the threshold and a black pixel region includes a pixel with a high luminance value is captured, the captured scene is classified as a night scene.

  When the scene classification unit 31 classifies the captured scene as a night scene, the scene classification unit 31 determines whether or not the subject includes fireworks based on the captured image.

  FIG. 4 is a diagram illustrating a method for determining whether or not a subject includes fireworks. The vertical axis in FIG. 4 represents time, and the four images shown on the left are live view images. In FIG. 4, the position on the image will be described with the upper left corner of each image as the reference (0, 0).

  The scene classification unit 31 analyzes the image taken at time t0, the coordinates of the brightest block (collection of pixels) are near (5, 5), and the average brightness of the entire image is different from that of other images. It is detected that it is relatively brighter than that. In addition, the scene classification unit 31 analyzes an image captured at time t1 after a predetermined time has elapsed from time t0, the coordinates of the brightest block are unknown, and the average brightness of the entire image is different from that of other images. It is detected that it is relatively dark compared to it. The image taken at time t1 shows fireworks immediately after launch.

  Similarly, the scene classification unit 31 analyzes an image photographed at a time t2 after a lapse of a predetermined time from the time t1, and the coordinates of the brightest block are near (9, 6) or (2 1, 13). It is detected that the average brightness of the entire image is relatively bright compared to other images. The scene classification unit 31 analyzes an image taken at time t3 after a predetermined time has elapsed from time t2, and the coordinates of the brightest block are near (14, 5), and the average brightness of the entire image is other than It is detected that it is relatively brighter than the image of.

  For example, the scene classification unit 31 performs such an analysis, and based on the fact that the position of the brightest block in the image changes every moment and the brightness of the entire image changes every moment, Is determined to be included. Whether or not the subject contains fireworks is determined by either changing the position of the brightest block in the image or changing the brightness of the entire image. You may make it perform based on one side.

  In addition, when the photographing apparatus 1 is provided with a microphone, the volume of the sound collected by the microphone is analyzed by the scene classification unit 31, and when the brightness of the entire image is proportional to the volume, fireworks are generated on the subject. It may be determined that it is included. It is considered that the brighter the fireworks, the louder the sound of the audience, such as cheers and noises. Further, when a sensor for detecting the posture of the photographing apparatus 1 is provided, the posture of the photographing apparatus 1 detected by the sensor is parallel to the horizontal direction or facing upward (sky side). Alternatively, it may be determined that the subject includes fireworks. When shooting fireworks, the user usually takes a picture with the photographing device 1 facing above the horizontal.

  In this way, for example, it can be easily or accurately determined whether or not the subject includes fireworks.

  The scene classification unit 31 includes information on the shooting scenes classified as described above and information indicating whether or not the subject includes fireworks when the shooting scene is classified as a night scene. And output to the image processing unit 14.

  The face detection unit 32 analyzes an image captured for live view before the shutter button is pressed, and detects a human face from the captured image. For example, the face detection unit 32 detects a human face by matching a feature of a face prepared in advance with a feature of each area of a captured image. The face detection unit 32 outputs information indicating whether or not a human face is captured to the imaging control unit 33 and the image processing unit 14 according to the detection result.

  The shooting control unit 33 sets a shooting mode based on the information supplied from the scene classification unit 31 and the face detection unit 32, and when the user presses the shutter button, the CMOS sensor 12 and the flash 17 are set according to the set shooting mode. To control shooting.

  For example, when the scene classification unit 31 classifies the shooting scene as a night scene, the shooting control unit 33 sets continuous shooting to ON. When the shutter button is pressed by the user, the shooting control unit 33 controls the CMOS sensor 12 according to the setting and continuously takes a plurality of images.

  In addition, when the shooting scene is classified as a night scene and the human face is detected by the face detection unit 32, the shooting control unit 33 continuously displays a plurality of images in response to the user pressing the shutter button. When shooting, the strobe 17 is caused to emit light either at the first shooting or at the last shooting. The light of the strobe 17 illuminates the person, and the person is brightly reflected in the first or last image taken with the light emission of the strobe 17.

  Thus, in the photographing apparatus 1, when the photographing scene is classified as a night scene, the photographing mode is set so that continuous photographing is performed. Also, when the shooting scene is classified as a night scene, when a human face is detected, either the first shooting or the last shooting of a plurality of consecutive shootings The shooting mode is set so that the flash 17 emits light.

[About processing in the image processing unit 14]
Here, switching of processing by the image processing unit 14 will be described. In the image processing unit 14, processing performed using the image captured as described above when the shutter button is pressed by the user is switched according to the determination result by the scene classification unit 31 and the face detection unit 32. .

<When it is a night scene and fireworks are reflected>
When the shooting scene is a night scene and fireworks are shown, a plurality of images shot by the continuous shooting function are supplied to the image processing unit 14.

  In this case, the image processing unit 14 synthesizes a plurality of images taken by the continuous shooting function by maximum value synthesis to generate one synthesized image. Maximum value composition is the pixel value of the pixel with the highest pixel value among the corresponding pixels (pixels with the same coordinates on each image) of a plurality of images captured by the continuous shooting function. Is a process of combining a plurality of images. Here, a description will be given of a case where the composition is performed so that the pixel value of the pixel with the highest pixel value is the pixel value of each pixel of the composite image, but the pixel value of the pixel with the highest luminance value is It is also possible to use pixel values.

FIG. 5 is a diagram for explaining the maximum value synthesis. Images P1 to P3 shown on the left side of FIG. 5 are images taken in that order by the continuous shooting function, and the image shown on the right side is a composite image. The case where the pixel value of each pixel at the position of the coordinates (x ₁ , y ₁ ), (x ₂ , y ₂ ), (x ₃ , y ₃ ) of the composite image is described will be described.

The image processing unit 14, when obtaining the pixel value of the pixel of the coordinates of the synthesized image _(x 1, _{y 1),} the pixel values of the pixels of the coordinates of the image P1 _(x 1, _{y 1),} coordinates of the image P2 (x ₁ , y ₁ ) and the pixel value of the pixel (x ₁ , y ₁ ) of the image P3 are compared, and the pixel value of the pixel having the maximum pixel value is compared with the coordinate ( x ₁ , y ₁ ) are selected as pixel values. In the example of FIG. 5, as indicated by the tip of arrow # 11, the pixel value of the pixel at the coordinate (x ₁ , y ₁ ) of the composite image is used as the pixel value of the pixel at the coordinate (x ₁ , y ₁ ) of the image P1. A value is selected.

Further, the image processing unit 14, when obtaining the pixel value of the pixel of the coordinates of the synthesized image _(x 2, _{y 2),} the pixel value of the pixel coordinates of the image P1 _(x 2, _{y 2),} the coordinates of the image P2 and pixel values of pixels (x _{2, y 2),} with the pixel values of the pixels of the coordinates of the image P3 (x _{2, y 2),} the pixel value of the pixel in which the pixel value is maximized, the composite image The pixel value of the pixel at coordinates (x ₂ , y ₂ ) is selected. In the example of FIG. 5, as indicated by the tip of arrow # 12, the pixel value of the pixel at the coordinate (x ₂ , y ₂ ) of the composite image is used as the pixel value of the pixel at the coordinate (x ₂ , y ₂ ) of the image P2. A value is selected.

Similarly, the image processing unit 14, when obtaining the pixel value of the pixel of the coordinates of the synthesized image _{(x 3, y} 3), and the pixel value of the pixel coordinates of the image _{P1 (x 3, y 3)} , the image P2 coordinates and a pixel value of a pixel of the (x _{3, y 3),} with the pixel values of the pixels of the coordinates of the image _{P3 (x 3, y 3)} , the pixel value of the pixel having a pixel value of the maximum, the composite image Is selected as the pixel value of the pixel at the coordinates (x ₃ , y ₃ ). In the example of FIG. 5, as indicated by the tip of arrow # 13, the pixel value of the pixel at the coordinate (x ₃ , y ₃ ) of the composite image is used as the pixel value of the pixel at the coordinate (x ₃ , y ₃ ) of the image P3. A value is selected.

  When the shooting scene is a night scene and fireworks are captured, the image processing unit 14 combines a plurality of images shot by the continuous shooting function by such maximum value synthesis to generate one synthesized image. . For example, when the pixel value of each pixel is represented by 8 bits and white is represented by RGB = (255, 255, 255), the image is such that each image alone is underexposed. However, the composition is performed so as to collect bright pixels of the plurality of images, and it is possible to obtain a composite image in which the fireworks part is appropriately exposed. In other words, in fireworks shooting, it is common to shoot with long exposure settings in order to leave underexposure and flash trajectory, but if you do not select the proper time, it will be overexposed and you will lose detail and contrast. . Therefore, by using the continuous shooting and the maximum value composition as described above, it is possible to make the fireworks have an appropriate exposure while suppressing overexposure.

<When it is a night scene and fireworks are not reflected>
Even when the shooting scene is a night scene and no fireworks are shown, a plurality of images shot by the continuous shooting function are supplied to the image processing unit 14 as in the case where fireworks are shown.

  In this case, the image processing unit 14 synthesizes a plurality of images taken by the continuous shooting function by addition synthesis or average synthesis to generate one synthesized image. Additive synthesis is a process of synthesizing a plurality of images so that the sum of the pixel values of corresponding pixels of the plurality of images taken by the continuous shooting function is used as the pixel value of each pixel of the synthesized image. In addition, when adding and synthesizing, if the pixel value becomes a value exceeding an upper limit value (for example, 255) as a result of the addition, the pixel value of the entire image may be reduced at a ratio that the largest value becomes the upper limit value. it can.

  On the other hand, the average synthesis is a process of synthesizing a plurality of images so that an average of pixel values of corresponding pixels of a plurality of images taken by the continuous shooting function is used as a pixel value of each pixel of the synthesized image. The average composition is selected when, for example, the ratio of the pixels whose pixel values are saturated and whiteout exceeds a predetermined ratio in a composite image obtained by addition composition.

  When the shooting scene is a night scene and no fireworks are captured, the image processing unit 14 combines a plurality of images shot by the continuous shooting function by such addition synthesis or average synthesis, and combines one synthesized image. Generate. As a result, it is possible to obtain a composite image in which a night scene is captured with an appropriate exposure. It is also possible to perform camera shake correction on a plurality of images taken by the continuous shooting function, and to perform addition synthesis or average synthesis based on the image after camera shake correction.

<When a human face is detected>
When the shooting scene is a night scene and a person's face is captured, a plurality of images shot by the continuous shooting function are supplied to the image processing unit 14. Of the plurality of images supplied to the image processing unit 14, the first or last captured image is an image captured with the flash 17 emitting light.

  FIG. 6 is a diagram for explaining the flow of extraction of a person region. As indicated by the tip of the arrow # 21, the image processing unit 14 includes an image shot without the flash 17 and among the plurality of images shot by the continuous shooting function, and the flash of the flash 17 at the beginning or end. The difference in luminance value from the image taken in is obtained, and mask data is generated. The mask data is used to extract a person region from an image taken with the flash 17 emitting light.

  Hereinafter, as appropriate, an image photographed with the flash 17 emitting light is referred to as a strobe ON image, and an image photographed without the strobe light emitting is referred to as a strobe OFF image.

  As shown in FIG. 7, a case where a person is photographed with fireworks in the background will be described. When shooting is performed with the flash 17 emitting light, the luminance value of the person area in the image obtained by the shooting is higher than the luminance value of the background area. On the other hand, when shooting is performed without the flash 17 emitting light, the luminance value of the person area in the image obtained by the shooting is low, as is the luminance value of the background area.

  The image processing unit 14 obtains a difference in luminance value for each region of the strobe ON image and the strobe OFF image, and generates mask data as shown in FIG. 8 indicating a region where the difference in luminance value is equal to or greater than a threshold value. In the mask data shown in FIG. 8, a hatched area is an area where the difference between the brightness values of the strobe ON image and the strobe OFF image is equal to or greater than a threshold value, and corresponds to a person area.

  After generating the mask data, the image processing unit 14 corrects the mask data as indicated by the tip of arrow # 22 in FIG. Correction of mask data is a part of a person but is not detected as a person area in the mask data because the light from the strobe 17 does not strike (the difference between the brightness values of the strobe ON image and the strobe OFF image exceeds a threshold value) This is a process for processing the mask data so as to include the non-applicable part) in the person area.

  For example, even if shooting is performed with the flash 17 emitting light, the light may not reach the top of the person's head. In this case, the shape of the head portion of the person area of the mask data is a concave shape as shown by being surrounded by a broken-line circle in FIG. The image processing unit 14 corrects the mask data so that the recessed shape becomes a shape that is not recessed as shown in FIG. The range of the entire head can be predicted based on the position of the face detected by the face detection unit 32. For example, the image processing unit 14 predicts the range of the entire head and corrects the mask data. .

  After correcting the mask data, the image processing unit 14 uses the mask data to extract a person area from the strobe ON image, as indicated by the tip of arrow # 23 and arrow # 25 in FIG. When the mask data is overlaid, the area on the image corresponding to the hatched area in FIG. 8 becomes the person area shown in the strobe ON image.

  After extracting the person area from the strobe ON image, as shown by the tip of arrow # 24 in FIG. 6, the image processing unit 14 combines the person area image into a composite image in accordance with the blend map. As described above, the composite image that is the composition destination of the person's area is an image generated by the maximum value composition when the shooting scene is a night scene and the fireworks are captured, and the fireworks are not captured Is an image generated by addition synthesis or average synthesis.

  FIG. 10 is a diagram showing an example of a blend map. The horizontal axis in FIG. 10 represents the difference between the brightness values of the strobe ON image and the strobe OFF image, and the vertical axis represents the composition ratio of the pixel values of the person area extracted from the strobe ON image. For example, if the composition ratio is 50%, the pixel value of the pixel in the region of the person in the finally obtained composite image is the pixel value of the pixel in the composite image and the person extracted from the strobe ON image. This means that pixel values obtained by mixing the pixel values of the pixels in the region by 50% are used.

  In the example of FIG. 10, when the difference between the brightness values of the strobe ON image and the strobe OFF image is equal to or smaller than the threshold value 1, the composition ratio of the pixel values of the person area extracted from the strobe ON image is set to 0%. ing. When the difference in luminance value is greater than or equal to the threshold value 1 and less than the threshold value 2, the composition ratio of the pixel values of the person region extracted from the strobe ON image is linearly 0 in proportion to the difference in luminance value. From 100% to 100%. Furthermore, when the difference in luminance value is equal to or greater than the threshold value 2, the composition ratio of the pixel values of the pixels in the person region extracted from the strobe ON image is 100%.

  Such blend map information is preset for the image processing unit 14. When the shooting scene is a night scene and a human face is captured, the image processing unit 14 combines the image of the person region extracted from the strobe ON image into a composite image according to the blend map.

  This makes it possible to obtain a composite image in which both the background and the person are exposed properly. As described above, the background is appropriately exposed by combining processing such as maximum value combining, addition combining, and average combining. In addition, the person is exposed properly by shooting with the flash 17 emitting light.

[Operation of the photographing apparatus 1]
Next, imaging processing of the imaging apparatus 1 will be described with reference to the flowcharts of FIGS. 11 and 12.

  In step S <b> 1, the shooting control unit 33 controls the CMOS sensor 12 to shoot a live view image. The captured live view image is stored in the memory 13, supplied to the scene classification unit 31 and the face detection unit 32, read out by the image processing unit 14, and displayed on the LCD 16.

  In step S2, the scene classification unit 31 analyzes the live view image and classifies the shooting scene. The scene classification unit 31 also detects whether or not fireworks are included in the subject when the shooting scene is classified as a night scene.

  In step S3, the face detection unit 32 analyzes the live view image and performs face detection.

  In step S4, the scene classification unit 31 determines whether or not the shooting scene is a night scene. If it is determined in step S4 that the shooting scene is not a night scene, the procedure proceeds to step S5, and the shooting control unit 33 performs normal shooting according to the shooting scene. That is, the shooting control unit 33 sets parameters according to a shooting scene such as a portrait scene or a landscape scene, and performs shooting when the shutter button is pressed. The captured image is subjected to various types of image processing by the image processing unit 14 and then supplied to the output unit 15. The output unit 15 records the image data on the recording medium, and then the normal photographing process is terminated.

  On the other hand, when it is determined in step S4 that the shooting scene is a night scene, the procedure proceeds to step S6, and the shooting control unit 33 sets continuous shooting to ON.

  In step S7, the imaging control unit 33 determines whether or not a human face has been detected by the face detection unit 32. If it is determined that a human face has been detected, the process proceeds to step S8, The strobe 17 is set to emit light at any time during the last shooting.

  In step S9, the imaging control unit 33 determines whether or not the shutter button has been pressed based on the signal supplied from the operation unit 18, and waits until it is determined that the shutter button has been pressed.

  In step S9, if the shooting control unit 33 determines that the shutter button has been pressed, the procedure proceeds to step S10, the CMOS sensor 12 is controlled, and a plurality of images are shot by the continuous shooting function. Further, the photographing control unit 33 causes the flash 17 to emit light either at the first photographing or at the last photographing. A plurality of images taken by the continuous shooting function are stored in the memory 13 and then supplied to the image processing unit 14.

  In step S11, as described above, the image processing unit 14 generates mask data based on the difference between the brightness values of the strobe ON image and the strobe OFF image, and appropriately corrects the mask data (FIGS. 8 and 9). Is used to extract the image of the person area from the strobe ON image.

  In step S12, the image processing unit 14 determines whether or not fireworks are detected by the scene classification unit 31, and when it is determined that fireworks are detected, the process proceeds to step S13, and a plurality of images are combined by maximum value synthesis. Then, the image of the person region extracted from the strobe ON image is synthesized with the obtained synthesized image. The combined image data obtained by combining the image of the person region extracted from the strobe ON image is supplied from the image processing unit 14 to the output unit 15.

  In step S14, the output unit 15 records the composite image data generated by the image processing unit 14 on a recording medium, and ends the process.

  When it is determined in step S12 that no fireworks are detected, the process proceeds to step S15, and the image processing unit 14 combines a plurality of images by addition synthesis or average synthesis, and the obtained synthesized image is a strobe ON image. The image of the person area extracted from is synthesized. Thereafter, the process proceeds to step S14, and after the composite image is recorded, the process is terminated.

  If it is determined in step S7 that the human face has not been detected, the shooting control unit 33 proceeds to step S16 (FIG. 12), determines whether or not the shutter button has been pressed, and until it is determined that the button has been pressed. stand by.

  If it is determined in step S16 that the shutter button has been pressed, the shooting control unit 33 proceeds to step S17, controls the CMOS sensor 12, and takes a plurality of images using the continuous shooting function. Since no human face is detected, the flash 17 does not emit light here. A plurality of images taken by the continuous shooting function are stored in the memory 13 and then supplied to the image processing unit 14.

  In step S18, the image processing unit 14 determines whether or not fireworks are detected by the scene classification unit 31, and when it is determined that fireworks are detected, the process proceeds to step S19, and a plurality of images are combined by maximum value synthesis. . The synthesized image data generated by the maximum value synthesis is supplied from the image processing unit 14 to the output unit 15.

  In step S20, the output unit 15 records the composite image data generated by the image processing unit 14 on a recording medium, and ends the process.

  On the other hand, if it is determined in step S18 that no fireworks are detected, the image processing unit 14 proceeds to step S21, and combines a plurality of captured images by addition synthesis or average synthesis. Thereafter, in step S20, after the composite image is recorded, the process ends.

[Effects of the embodiment of the invention]
1. As described above, since the shooting scenes are classified before the shutter button is operated, when the shooting scene is a scene including a night view, it is easy to set the shooting mode to perform continuous shooting. Is possible.

  2. When fireworks are captured in a night scene, the pixel value of the pixel with the highest pixel value or luminance value among the corresponding pixels of multiple images taken with the continuous shooting function is used as the pixel value of each pixel of the composite image. Since a plurality of images are combined as described above, it is possible to easily shoot a night scene with good image quality in which the fireworks part is properly exposed.

  3. When fireworks are not captured in the night scene, the sum of the pixel values of the corresponding pixels of the plurality of images captured by the continuous shooting function is used as the pixel value of each pixel of the composite image, or the plurality of images When the ratio of pixels in which the sum of the pixel values of the corresponding pixels exceeds the threshold exceeds a predetermined ratio, the average value of the pixel values of the corresponding pixels of the plurality of images is set as the pixel value of each pixel of the composite image In addition, since a plurality of images are combined, it is possible to easily shoot a night scene with good exposure and good image quality.

  4). When a person's face is detected, the flash is fired when the first image of the plurality of images is shot or when the last image is shot. Since the irradiated area is extracted and the extracted area is superimposed on the composite image, it is possible to easily shoot a night scene with good image quality that is adequately exposed and free from camera shake. Therefore, it becomes possible to photograph a person with an optimum image quality.

  The series of processes described above can be executed by hardware or can be executed by software. When a series of processing is executed by software, a program constituting the software executes various functions by installing a computer incorporated in dedicated hardware or various programs. For example, it is installed from a program recording medium in a general-purpose personal computer or the like.

  The present invention is not limited to the above-described embodiment as it is, and in the implementation stage, the component may be modified and embodied without departing from the spirit of the invention, or a plurality of components disclosed in the above-described embodiment. Various inventions can be formed by appropriately combining the above. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine the component covering different embodiment suitably.

1 Camera 11 CPU
12 CMOS sensor 13 Memory 14 Image processing unit 15 Output unit 16 LCD
17 Strobe 18 Operation Unit 31 Scene Classification Unit 32 Face Detection Unit 33 Shooting Control Unit

Claims (7)

Photographing means;
Scene classification means for analyzing an image photographed by the photographing means before a shutter button is operated, and classifying a scene being photographed;
When the scene classified by the scene classification unit is a night scene that is a scene including a night view as a subject, the photographing unit is configured to continuously capture a plurality of images when the shutter button is operated. And a control means for controlling the imaging device. The imaging device according to claim 1,
The scene classification means determines whether or not shooting of fireworks is performed when the scene being shot is classified as the night scene.
If it is determined that fireworks are being shot, the pixel value of the pixel having the highest pixel value or luminance value is selected from the corresponding pixels of the plurality of images shot when the shutter button is operated. An imaging apparatus, further comprising: an image processing unit that combines the plurality of images so as to obtain a pixel value of each pixel of the combined image. The imaging device according to claim 2,
When it is determined that no fireworks are shot, the image processing means calculates a sum of pixel values of corresponding pixels of the plurality of images after camera shake correction that is shot when the shutter button is operated. Corresponding to the plurality of images so as to be the pixel value of each pixel of the composite image, or when the ratio of pixels in which the sum of pixel values of corresponding pixels of the plurality of images exceeds a threshold exceeds a predetermined ratio The plurality of images are combined so that an average value of pixel values of pixels to be used is a pixel value of each pixel of the combined image. In the imaging device according to claim 2 or 3,
Face detection means for detecting a human face from an image photographed by the photographing means;
And a flash means for emitting a flash,
When the face detection unit detects a person's face from an image captured before the shutter button is operated, the control unit is configured to capture the first image of the plurality of images or the last Controlling the light emitting means to emit a strobe when taking an image,
The image processing unit extracts a region irradiated with a strobe from the first image or the last image, and superimposes the extracted region on the composite image. The imaging device according to claim 1,
Face detection means for detecting a human face from an image photographed by the photographing means;
And a flash means for emitting a flash,
When the face detection unit detects a person's face from an image captured before the shutter button is operated, the control unit is configured to capture the first image of the plurality of images or the last An image-taking apparatus, wherein the light-emitting means is controlled to emit a strobe when an image is taken. In a photographing method of a photographing apparatus provided with photographing means,
A scene classification step of analyzing an image photographed by the photographing means before a shutter button is operated, and classifying a scene being photographed;
When the scene classified by the process of the scene classification step is a night scene that is a scene including a night scene as a subject, the plurality of images are continuously captured when the shutter button is operated. And a control step for controlling the photographing means. In a program for causing a computer to execute a photographing process of a photographing apparatus including a photographing unit,
A scene classification step of analyzing an image photographed by the photographing means before a shutter button is operated, and classifying a scene being photographed;
When the scene classified by the process of the scene classification step is a night scene that is a scene including a night scene as a subject, the plurality of images are continuously captured when the shutter button is operated. A program for causing a computer to execute a process including a control step for controlling the photographing means.